MathDB

Let

101

marbles be numbered from

1

101

. The marbles are divided over two baskets

A

and

B

. The marble numbered

40

is in basket

A

. When this marble is removed from basket

A

and put in

B

, the averages of the numbers

A

and

B

both increase by

\frac{1}{4}

. How many marbles were there originally in basket

A?

3